Ladder webbing



Aug. 26, 1941.

' R. FRENCH LADDER WEBBING Filed Aug. 1 4, 1940 Patented Aug. 26, 1941 LADDER WEBBING p Roger French, Manchester, England Application August 14, 1940, Serial No. 352,54 In Great Britain August 23, 1939 11 Claims.

This invention relates to ladder webbing, such for example, as is used for Venetian blinds.

As known hitherto, such ladder webbing has comprised two outer woven webs or bandings and one or more rows of cross-straps between them, the cross-straps being composed of Warp and weft, or warp only, and in all cases woven into the respective outer webs at their ends.

The object of this invention is to provide improved forms of such type of ladder webbing which will allow of more than one set or lot of blind laths or slats being fitted to the webbing, and with the overlap of one set or lot intermediate of the overlap of the other set or lot, thereby more eifectively shutting out light and (or) controlling the fiow of air through the blinds, than the ordinary make of blind webbing fi-tted with only one set or lot of laths or s/lats.

According to the invention, ladder webbing is made to comprise at least three bandings, and has a row or rows of cross-straps between each pair of ladjacent bindings. Two of the bandings will, of course, be the outer bandings, and the other or others will be intermediate the outer bandings. All the bandings may be of the same width, or some (for example the outer ones) may be wider than the others.

The cross-straps (whichmay be weftless) will usually be arranged so that a row of straps on one side of an intermediate banding will be in line with a row of straps on the other side of such banding,'but this arrangement may be modified as desired. Further, the number of rows of straps between one pair of bandings may diifer from that between an adjacent 'pair of bandings.

According to another feature of the invention, cross-straps which are joined to opposite sides of an intermediate banding are arranged to meet the banding at .the same point in its length, and they may be disposed so that, either the crossstraps between the bandings of adjacent pairs are, when the webbing is opened'out, in the same lines viewed edgewise, or the cross-straps between the bandings of adjacent pairs are, when the webbing is opened out, inclined to the intermediate webbing in opposite directions.

another group is present only in the other strap of the pair, both groups being woven into or onto the intermediate banding.

When it is not desired that cross-straps on opposite sides of an intermediate banding meet that banding at the same point, all the crossstraps may -be made by the same warp threads, which Warp straps will be woven into or onto the intermediate banding between the inner ends of the straps.

When the cross-straps on opposite sides of an intermediate banding are to join the banding at the same point, one group of\\strapravarp threads may form all the straps on one side of the banding, whilst another group will form all the straps on the other side of the banding. A1- ternatively, a cross-Strap on one side of an intermediate banding may be made-from one group of Warp threads, which, after being woven in .the banding for a distance Will make the cross-Strap on the other side of the banding in the next succeeding pair.

In all cases, where Strap-Warp threads from the same group appear in both of two adjacent banding spaces, the usual cross-over between the ends of successive bindings-in will be arranged to pass through the intermediate banding.

In the .accompanying drawing:

Fig. 1 is a diagrammatic side view of one example of the improved webbng, and

Figs. 2 to 5 are like views of other examples of the improved webbing.-

In one example shown in Fig. 1, there are three bandings, a, b, c, one central to the other two, and between the bandings a, b, at the crossstraps d, whilst between the bandings b, c, are the cross-straps e. With the cross-straps d not in edgewise alignment with the cross-Strap e, but inclined in the same direction, .there is one group only of cross-Warp threads for both lots of cross-straps. These are first bound into, or on, say, the outer banding a, then extend to the banding b, and into, or on such bandin'g they are then bound. They then extend to the outer banding c to form a cross-Strap e, into, or on which banding they are bound. The said strapwarp threads now cross back to the outer banding a, by passing through the intermediate banding b, when the cycle begins again, this last crossover being the usual cross-over between successive blndings-in and requiring to be snipped before the webbing can be opene'd out.

- In Fig. 2, there are the same vthree bandings a, b, c, and the cross-straps d, e, are in edgewise alignment, but instead of the cross-Strap warps being bound into the intermediate banding b, they simply pass directly through it to form the cross-straps d and e, being bound only into, or on the bandings a, c, and after each binding-in with the banding c, passing back to the banding a, for the next banding-in, when the cycle is repeated. In this example, the cross-straps if weftless are not rigidly connected to the intermediate banding b, although due to the tightness of the weave of the banding b. they remain uput" with ordinary use.

In Fig. 3, there are three bandings, a, b, c but, instead of one group of warp threads for both rows of cross-straps d, e, there are two groups. One group is first bound into, or on say the outer banding a, then extends to the banding b, to form a cross-Strap d, and is then bound into the banding b up to the next succeeding crossstrap d into the same row, whereupon it extends to the outer banding c to form another cross- Strap e between the bandings band c and is then bound into or on the banding c. After such binding-in, the warp threads pass directly back to the banding a, when the cycle is repeated. The other group of Strap-Warp threads is similarly first bound to the banding a, then crosses over to form another cross-Strap d, is then bound into, or on the banding b, and then crosses over to the banding c, into, or to which the warp threads are bound, prior to crossing directly back through the banding b to the banding a, into, or on which they are bound, prior to repeating the cycle. In this way, each alternate cross-Strap in each row is formed by one group of Warp threads, and each intermediate crossstrap in each row is formed by the other group.

In Fig. 4, there are again two groups of crossstrap Warp threads for each row of cross-straps, one of which, after being bound into or on say the banding a, extends to the banding b to form a weftless cross-Strap d, is then bound into or on the banding b for say half the distance between successive straps d, d, and then crosses back to the banding a and is bound thereto, or thereon, until the next strap d begins. The other group of cross-Strap warps, having been .bound with the banding b to the point where the first strap d terminates, then extends to the outer banding c to form a cross-Strap e, and after being bound therein or thereto, crosses directly back to the banding b to which it is then bound until the next strap e begins. It will be seen that with this arrangement one group of cross-Strap warp threads makes all the straps d on one side of the banding b, whilst v the other group makes all the straps e on the other side of the banding b.

In Fig. 5, there are also two groups of crossstrap Warp threads for the two rows of crossstraps d, e. Both groups are first bound'into the banding b at the same place, and then separated, one passing to the outer banding a, and the other passing to the outer banding c to form cross-straps, d, e, and after being bound into or on to the respective outer bandings, for an equal distance, crossing back to the banding b, when the cycle is repeated.

In the last two examples, the cross-Strap Warp threads in either group are only lifted the dis-- tance between any two bandings, and thus afford advantages in the weaving Operations. For example, a less number of lifts is required in the dobby, and (or) a smaller dobby may be employed, with consequent reduction in power reaaa-1,008

quired and in wear and tear on the loom. As aforesaid, the cross-straps may consist of warns only, or warp and weft, and when composed of Warp and weft, the weft will either be interwoven with the banding, or be left free to float between the points where the warps enter and leave the bandings. Usually in the case of the examples shown in Figs. 3 and 4, the crossstraps will be weftless. It is, of course, to be understood that the weaving of the bandings will progress simultaneously and at the same speed, and the cross-straps will be incorporated therewith (bound thereto) in like manner to those of ordinary known webbing.

In all cases, there will usually be two separate rows of cross-straps between bandings a, b and also between bandings b, c, and, as usual, those in one row lying in staggered relationship to those in the other row. There may, however, be a composite row or rows and the bindings-in may be of extended length according to prior Patent -No. 2.141,038, dated Dec. 20, 1938, entitled Triple warp ladder web, and (or) prior pending Patent No. 2,238,4=65, dated April 15, 1941, entitled Ladder web.

When the outer bandings a, c, are to be of different colours, or the strap warps are to be of a different colour from the bandings, the bindings-in may be characterised according to any of the forms set\forth in the specification of Patent No. 2,194,440,`-dated March 19, 1940, entitled Ladder web with double weft, or the specification of pending application Serial No. 281,228, filed June 26, 1939, entitled Ladder webbing.

What I claim is:

1. Ladder webbing, characterised by being composed of at least three bandings composed of woven warp and weft, two of which are outer bandings and at least one is an intermediate banding, cross-straps including warp threads between each of the outer and the intermediate bandings, said warp threads being woven into at least some of said bandings.

2. Ladder webbing as claimed in claim 1, wherein are three bandings, one central to the other two and all three produced simultaneously, also wherein a single group of cross-Strap Warp threads is used to form cross-straps between each pair of adjacent bandings, such group being first bound into or on one outer banding, then passing over to the middle banding to form a cross-Strap, then being bound into or on the middle banding, and then passing over to the other outer banding., into or on which it is bound, and finally crossing back to the firstnamed outer banding via the middle banding.

3. Ladder webbing as claimed in claim 1, wherein are at least three bandings spaced apart and produced simultaneously, also wherein a single group of cross-Strap warp threads is used to form cross-straps between each pair of adjacent bandings, such group, after being bound into or on one outer banding, passing to the other outer banding through the intermediate banding '(or bandings) to form weftless crossstraps, then being bound into or on such other outer banding and finally passing back to the first-named outer banding via the intermediate banding (or bandings).

4. Ladder webbing as claimed in claim 1, wherein are three bandings produced simultaneously and one central to the other two, also wherein two groups of cross-Strap Warp threads are used to form a row of cross-straps between each pair of adjacent bandings, each group being 'l Ladder webbing as claimed in claim 1,

threads lying in edgewise alignment with those in the other row.

5. Ladder webbing as claimed in claim gl, wherein are three bandings produced simultaneously and one central to the other two, also wherein one group of cross-Strap warp threads' is used to form a row of cross-straps between one pair of adjacent bandings, and a separate group I to form a row of cross-straps between the other pair, each group being flrst bound into or on an outer banding, then crossing over to the middle banding to form a cross-Strap, then being bound into or on the middle banding for a distance equal to the required spacing apart of the crossstraps, and then again passing over to the firstnamed outer banding,` when the cycle is repeatei, the several cross-straps in the two rows lying in edgewise alignment.

6. Ladder webbing as claimed in claim 1. wherein are three bandings produced simultaneously and one central to the other two, also wherein one group of cross-Strap Warp threads is used to form arow of cross-straps between one pair of adjacent bandings, and a separate group to form a row of cross-straps between the other pair, each group being first bound into or on an outer banding, then crossing over to the middle banding to form a cross-Strap, then being bound into or onthe middle banding for a distance equal to the required spacing apart of the cross-straps, and then again passing over to the flrst-named outer banding, when the cycle is repeated, the several cross-strapsin one row extending in a direction opposite to those in the other row.

wherein-are at least three bandings produced simultaneously, and a row (or rows) of crossstraps between each pair of adjacent bandings,

and-wherein each group' of cross-Strap warp threads, comprises two or more sets or lots, whereby the bindings-in may vary in length without aifecting the distance between successive cross-straps of the same row.

8. Ladder webbing as claimed in claim '1, wherein one of the outer bandings is of different colour than the other outer banding, -and wherein alternate warp threads in the cross-straps are of the same color as said outer banding, and are alone bound mto such banding, whilst the intermediate warp threads in the cross-straps,

which are the colour of the other outer banding, are merely bound on to the inner face of the firt-named banding.

9. Venetian' blind and like ladder webbing as claimed in claiml, wherein one or both of the outer bandings is of one colour and the cross- Strap warps of another colour, and wherein each outer banding is woven with two wefts in each Warp shed, and the strap warps are bound to the inner faces of the outer bandings by alternate banding wefts, and are covered by the intermedate banding wefts.

10. Ladder webbing -according to claim 1, wherein are more than two bandings, and a row ofcross-straps between each pair of adjaoent bandings, said cross-straps in each row being produced'by at least two separate sets of warp threads and each set. after being bound into, or on a banding, passing through the next succeeding cross-strap, the several cross-straps forming a single composite row, equal to the ROGER FRENCH. 

